Light-emitting element driving circuit system

1. A light-emitting element driving circuit system in which a plurality of current paths, in each of which a light-emitting element and a switching element which is controlled to be switched ON and OFF for causing light to be emitted from the light-emitting element are connected in series, are placed in parallel to each other, wherein an ON time of each switching element is adjusted based on a light-emission period which is a period in which the light-emitting elements are caused to emit light in a circulating manner, such that a number of switching operations of each switching element is reduced.

2. The light-emitting element driving circuit according to claim 1 , wherein the ON time of each switching element is adjusted such that a time period obtained by dividing the light-emission period by a total number of the plurality of the light-emitting elements is set as the ON time of each switching element.

3. The light-emitting element driving circuit system according to claim 2 , wherein when the light-emission period is changed, the control to switch ON and OFF is changed such that a time period obtained by dividing the light-emission period after the change by the total number of the plurality of the light-emitting elements is set as the ON time of each switching element.

4. A portable phone comprising: a light-emitting element driving circuit system in which a plurality of current paths, in each of which a light-emitting element and a switching element which is controlled to be switched ON and OFF for causing light to be emitted from the light-emitting element are connected in series, are placed in parallel to each other, wherein an ON time of each switching element is adjusted based on a light-emission period which is a period in which the light-emitting elements are caused to emit light in a circulating manner, such that a number of switching operations of each switching element is reduced.